Developers spent a record-breaking $917,375 on a failed ballot measure that would have allowed them to bypass Mendocino County's planning process and build the county's largest commercial development.

Ohio-based Developers Diversified Realty and Texas businessman David Berndt last year invested almost $102 for each of the 9,022 "yes" votes they won, only to see nearly 2 of every 3 voters reject their plan.

Measure A opponents spent $107,135, or $7 for each of the 15,292 votes that defeated the measure, according to final campaign reports filed Monday.

The ballot box battle over the Ukiah Valley's planning process slashed the previous record held by a 2004 ballot measure that banned production of genetically modified crops in the county.

During that ballot campaign, agribusiness corporations spent almost $688,000 in a futile effort to defeat Measure H. Measure H proponents spent just over $145,000.

Measure A would have freed developers to build up to 800,000 square feet of retail stores and other commercial buildings on 80 acres at the former Masonite plant property just outside Ukiah without going through the county planning process.

Developers Diversified officials have yet to divulge what they plan to do next with the property, which they purchased for $6.5 million in 2006. They reportedly are in negotiations to sell a portion of the land to Costco.

Developers Diversified took the project to voters last year, saying the county process was too cumbersome and lengthy. They also said they did not believe the current county Board of Supervisors would approve the project.

Opponents of the project called the ballot measure an end run around county and environmental regulations.

Developers Diversified has been speaking with county officials but has yet to submit plans for a project, said Planning Director Nash Gonzalez.